Ohio Earthquakes, 1983-1985
(from Fall 1985 Ohio Geology)
From 1983 through 1985, 13 small earthquakes have been recorded in the state of Ohio by the Seismological Observatory of the University of Michigan. In addition, two small earthquakes, one of which was felt in part of Ohio, occurred in the border-region of the state.
Four earthquakes in 1983 were from the same location in eastern Shelby County at the site of six small earthquakes in 1980 and 1981. The 1983 quakes, along with the earlier ones, all measured about 2.0 or less on the Richter scale--too small to be felt locally. The significance of this cluster of micro earthquakes is uncertain, but this general area has been the source of at least 35 earthquakes that were felt by local residents, including two damaging events in March 1937. Two micro earthquakes occurred in 1985 in western Auglaize County, near the epicenters of the 1937 quakes, which were the most intense ones ever recorded in Ohio. It is probable that numerous other micro earthquakes have occurred in this area, but it was not until the establishment of the "Anna array" of seismographs by the University of Michigan in the late 1970's that such small events could be recorded.
A small earthquake, apparently not felt by local residents, was recorded in 1983 near Hamilton on the Hamilton-Butler County line. This general area has been the source of five earthquakes that were felt locally in the 1920's and 1930's.
Two earthquakes, one in late 1983 and one in early 1984, were recorded in the Toledo area in Lucas County; one of these, with a Richter magnitude of 2.6, was felt by local residents. Newspaper reports indicated that the principal phenomenon experienced by numerous individuals during this quake was the rattling of dishes. Lucas County has been the site of four previous felt earthquakes, which occurred in the 1920's, 1940's, and 1950's.
A small earthquake was recorded instrumentally beneath Lake Erie, offshore from Lake County in northeastern Ohio, in 1983. Although this earthquake had a Richter magnitude of 2.7, large enough to be felt locally, no residents along the Lake Erie shoreline reported any vibratory phenomena. In part, this circumstance may be related to the occurrence of this earthquake in the early morning hours. Northeastern Ohio, including Lake County, has been the site of numerous small earthquakes.
Putnam County was the site of a small earthquake in 1985, near the location of two small earthquakes in 1981. A small earthquake also was recorded in 1985 in northern Fayette County.
Greenup County, Kentucky, in the Ohio border region, experienced a 3.7 Richter-magnitude earthquake in 1983 that was felt by many residents of Portsmouth in Scioto County. No damages were reported. This general region, the tristate area of Ohio, Kentucky, and West Virginia, has been the site of several small earthquakes in recent years.
An additional border-region event occurred in Mercer County, Pennsylvania, just east of the Trumbull County, Ohio line in 1983. This event had a Richter magnitude of 2.5; however, there were no reports from local residents of vibrations or other common earthquake phenomena. This earthquake was near the epicenter of a small earthquake in 1936. ---Michael C. Hansen
Recent Ohio Earthquakes
| Date (UTC) * |
Origin Time (UTC) |
Location |
Richter
Magnitude |
| Yr |
Mo |
Day |
Hr |
Min |
Sec |
Lat. °N |
Long. °W |
County |
| |
|
|
|
|
|
|
|
|
|
| 1983 |
01 |
12 |
02 |
49 |
41.1 |
39.28 |
84.60 |
Hamilton/Butler |
2.0 |
| 1983 |
01 |
22 |
07 |
46 |
57.9 |
41.85 |
81.19 |
Lake (offshore) |
2.7 |
| 1983 |
07 |
04 |
02 |
58 |
53.1 |
40.43 |
84.10 |
Shelby |
2.0-2.2 |
| 1983 |
07 |
12 |
01 |
17 |
34.8 |
40.43 |
84.10 |
Shelby |
1.2-1.5 |
| 1983 |
08 |
11 |
14 |
03 |
14.4 |
38.47 |
82.78 |
Greenup (Ky) |
3.7 |
| |
|
|
|
|
|
|
|
|
|
| 1983 |
09 |
30 |
02 |
33 |
44.8 |
41.59 |
84.33 |
Williams |
1.2-1.4 |
| 1983 |
11 |
04 |
21 |
00 |
59.8 |
40.43 |
84.10 |
Shelby |
0.3 |
| 1983 |
11 |
04 |
22 |
50 |
00.5 |
40.43 |
84.10 |
Shelby |
0.7 |
| 1983 |
12 |
07 |
22 |
57 |
01.6 |
41.70 |
83.50 |
Lucas |
2.0 |
| 1984 |
01 |
14 |
20 |
14 |
31.5 |
41.65 |
83.40 |
Lucas |
2.6 |
| |
|
|
|
|
|
|
|
|
|
| 1985 |
03 |
10 |
20 |
46 |
01.2 |
40.52 |
84.39 |
Auglaize |
1.4 |
| 1985 |
03 |
10 |
20 |
49 |
14.1 |
40.52 |
84.40 |
Auglaize |
1.7 |
| 1985 |
03 |
17 |
11 |
57 |
06.7 |
39.65 |
83.46 |
Fayette |
1.9 |
| 1985 |
04 |
14 |
11 |
39 |
51.3 |
41.40 |
80.37 |
Mercer (Pa) |
2.5 |
| 1985 |
08 |
25 |
16 |
27 |
11.9 |
40.97 |
84.22 |
Putnam |
1.5 |
|
Source: Douglas Christensen, University of Michigan Seismological Observatory
*UTC, Universal Coordinated Time, is equal to Greenwich Mean Time (GMT) and is used to standardize all earthquakes. To convert to local time (Eastern Standard Time) subtract 5 hours (4 hours for Daylight Savings Time)from UTC. Note that events that occur in early morning hours on UTC are listed a day later than local time.
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Ohio earthquakes, including border-region events, for the period 1983-1985.
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Further Reading
Hansen, M. C., 1985, Earthquakes in Ohio: Ohio Geological Survey Educational Leaflet 9..
Last update March 04, 2003
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